A conventional wireless access infrastructure includes a radio access network and a core network typically owned, managed, and controlled by a single wireless service provider called the wireless carrier. The radio access network, such as the Evolved Universal Terrestrial Radio Access (E-UTRA) defined in 3GPP's Long Term Evolution (LTE) standard, contains the network and equipment for connecting user equipment (UE), such as mobile devices and computers having wireless connectivity, to the core network. The core network, such as the Evolved Packet Core (EPC) defined in the LTE standard, contains the network and equipment for providing mobile voice and data services within the carrier's service environment and to external networks, such as the Internet, and other carriers' networks.
The LTE standard, for example, defines specific network nodes and communication interfaces for implementing the E-UTRA and EPC. According to the standard, the E-UTRAN includes one or more eNodeB (base stations) configured to communicate with UEs and the EPC core network. The EPC includes at least a Mobility Management Entity (MME), which manages session states, authentication, paging, and mobility and roaming functions; a packet-data gateway (PGW), which sends/receives data packets to/from an external data network, such as the Internet; a Serving Gateway (SG-W), which routes data packets between the PGW and an eNodeB; and a Policy and Charging Rules Function (PCRF), which manages users, applications, and network resources based on carrier-configured rules.
FIG. 1 is a schematic block diagram of an exemplary LTE wireless access infrastructure 1000 including an E-UTRAN 1100 and an EPC 1200. The E-UTRAN 1100 includes at least one eNodeB 1102 configured to communicate with UEs 1002A and 1002B over wireless links. The EPC 1200 contains network nodes including a MME 1202, SG-W 1204, PGW 1206, and PCRF 1208. While the exemplary infrastructure 1000 is depicted with only one PGW 1206 connected to an external packet-data network, such as the Internet, the EPC 1200 alternatively may contain multiple PGWs, each connecting the EPC 1200 to a different packet data network. The MME 1202, SG-W 1204, PGW 1206, and PCRF 1208 are implemented in software on dedicated hardware (computers) 1302, 1304, 1306, and 1308. The dedicated hardware may be a single server or a cluster of servers. The LTE network nodes 1202, 1204, 1206, and 1208 are typically implemented as monolithic software modules that execute on their respective dedicated hardware 1302, 1304, 1306, and 1308.
The LTE standard not only defines functionalities in each of the MME 1202, SG-W 1204, PGW 1206, and PCRF 1208, but also defines the communication interfaces between them. The LTE standard defines several interfaces including, for example, an “S1-MME” interface between the eNodeB 1102 and the MME 1202, an “S1-U” interface between the eNodeB 1102 and the SG-W 1204, an “S11” is an interface between the MME 1202 and the SG-W 1204, an “S5” interface between the SG-W 1204 and the PGW 1206, and a “Gx” interface between the PCRF 1208 and the PGW 1206. The exemplary infrastructure 1100 illustrates these standardized interfaces.
Because the communication interfaces and network nodes in the LTE wireless access infrastructure 1000 are standardized, they ensure compatibility between the MME 1202, SG-W 1204, PGW 1206, and PCRF 1208, even when those nodes are programmed and/or developed by different manufacturers. Such standardization also ensures backward compatibility with legacy versions of any nodes that may have been previously deployed in the infrastructure 1000.
The need for multiple, dedicated network nodes makes deployment of an LTE wireless access infrastructure, such as the exemplary infrastructure 1000, costly and complex. Specifically, IP-centric enterprise solutions with typical web-based interfaces and protocols do not generally work seamlessly with the 3GPP-based standardized functions and interfaces. For example, the interfaces of a typical Cloud-based service in the enterprise say, based on HTTPS are not easy to connect to 3GPP nodes with standardized interfaces such as S1 over SCTP. The standardized nodes and interfaces in conventional wireless access infrastructures also make scaling the infrastructure challenging. For example, it may be difficult to deploy only a subset of the functions and/or communication interfaces defined by the standard. Furthermore, conventional wireless access infrastructures may not utilize resources efficiently within the infrastructure. In some conventional wireless access solutions, for example, a UE may be denied voice and/or data services because one of the network nodes is unable to handle an additional user even though other nodes are not being fully utilized. In other words, the capacity of the conventional infrastructure may be limited by the capacity of each node.